"The U.S. already flunked the test and that should be a wakeup call," a former senior U.S. State Department official told Newsweek.

Fighting along the Thailand-Cambodia border has escalated, resulting in numerous casualties and mass displacement. China attributes the conflict's roots to historical Western colonialism, offering to mediate.

The latest flare-up started on Thursday, with intense fighting spreading across multiple border areas. Early Saturday, Thailand’s navy joined the army in repelling what it described as incursions by Cambodian troops at three points in eastern Trat province.

China has blamed “Western colonialists” for ongoing clashes on the Thai-Cambodian border that have left at least 15 people dead and forced tens of thousands to flee their homes.

Tensions have bubbled between the two neighbors for months, flaring on Thursday as Cambodia and Thailand exchanged fire.

Four dead as Tropical Storm Wipha tears through Thailand, China and into Vietnam - Heavy rain in China's eastern province of Shandong kills two people and leaves 10 missing

Thailand bombed Cambodia with F-16 fighter jets on Thursday, as relations between the two countries imploded following clashes on a disputed border near the Emerald Triangle.

China attempted a diplomatic thaw with India, but it was stymied by arms sales to Pakistan and disagreements over terrorism at the Shanghai Cooperation Organization’s leadership